1. Field of the Invention
This invention generally relates to laparoscopic surgical instruments and, in particular, to a system and method for actuating the tips of a laparoscopic surgical instrument.
2. Description of Prior Art
Laparoscopic surgical instruments or devices that use actuating blades or tips are typically activated by some mechanical means. In most cases, the surgical instruments or devices use an actuation rod to translate motion from a handle at one end to a tip at the opposite end of the device. Common to laparoscopic scissors and graspers is an actuation rod that includes a pin that works in conjunction with a slot in the tips. Moving the actuation rod cams the pin in the slot which opens and closes the tips.
The blades or tips typically have slots proximal to the pivot and because of this configuration, the back end of the blades or tips need to be quite large. When used on a grasper and the tips are in their open position, the back end of the tips extend out beyond the outside diameter of the grasper shaft and look like “wings.” This may be a problem for the user and, in particular, the patient as they can catch or interfere on tissue or other devices during use.
When used on scissors, these wings will most likely be covered up with a plastic shrink tubing to insulate all the metal components during electro-surgical cautery. However, when the blades or tips are open, the wings can stretch and deform the shrink tubing. This can be problematic in that when the scissors is withdrawn from the trocar, the deformed tubing may not relax and it may catch on the end of the cannula, thereby pulling the trocar out of the patient. Accordingly, there is a need in the art for an improved system and method for actuating the blades or tips of laparoscopic instruments so as to minimize the adverse wing effect.